1. Field of the Invention
The invention relates to a method and apparatus for increasing electrical brain activity, in particular the amplitude of P300 waves, thereby decreasing cravings for addictive substances by providing cranial electrical stimulation between the forehead and wrist area of a patient.
2. Description of the Related Art
P300 waves are electrical waves which occur in the human brain. They are a cognitive evoked potential in response to a stimulus to the brain known as an "oddball paradigm of beeps". The P300 wave occurs at approximately 300 ms from the initial stimulation of a patient with the oddball paradigm and are measured using a quantified EEG machine such as a device known as a BEAM ("Brain Electrical Activity Map"). The "P" stands for "Positive". Various researchers have correlated a diminished activity of P300 waves with an increase in craving for alcohol and other addictive drugs. See e.g., Begleiter & Projesz, Neuroele Processes in Individuals at Risk for Alcoholism, Alcohol & Alcoholism, Vol, 25:251-256 (1990); Begleiter, Projesz, Rawlinos & Echardt, Auditory Recovery Function and P3 in Boys at High Risk for Alcoholism, Alcohol, Vol. 4:315-321 (1987); Begleiter & Projesz, The P300 Component of the Event-Related Brain Potential in Psychiatric Patients, Evoked Potential, 529-535, New York: Alan R. Liss, Inc. (1986); Whipple, Parker & Noble, An Atypical Neurocognitive Profile in Alcoholic Fathers and Their Sons, Journal of Studies on Alcohol, Vol. 43:240-244 (1988); Polich, Burns, & Bloom, P300 and the Risk for Alcoholism. Clinical and Experimental Research, Vol. 12:248-254 (1988); Schukits, Gold, Croot, Finn & Polich, P300 Latency After Ethanol Inoestion in Sons of Alcoholics and in Controls. Biological Psychiatry, Vol. 24:310-315 (1988); O'Connor, Hesselbroch, Tasman, Depalma, P3 Amplitudes in Two Distinct Tasks are Decreased in Young Men with a History of Paternal Alcoholism, Alcohol Vol. 4:323-330 (1987). The amplitude of P300 waves is a measure of concentration, attention and anxiety. An increase in P300 wave amplitude probably has applications beyond a decrease in cravings for alcohol and drugs (i.e., reduction of anxiety, depression and insomnia).
Cranial Electrotherapy Stimulation ("CES") is a term applied by the U.S. Food and Drug Administration ("FDA") to the transcranial application of small amounts of electricity, usually less than 1.5 mA at 100 Hz, to the head of a human being. It was originally used in the 1960's to induce sleep.
Prior art applications of CES devices have involved the use of higher frequencies, e.g., Liss, whose device operates at 15 kHz, the electrodes being attached to the head at the temples by means of a headband device. Researchers have shown that CES at 1OO Hz is beneficial to alcoholics and drug abusers when attached to the mastoids. See, e.g., Smith, Cranial Electrotherapy Stimulation, Neural Stimulation, Vol. II: 129-150, Boca Raton, Fla., CRC Press Inc. (1985); Schmitt, Capo. Frazier & Cranial Electrotherapy Stimulation Treatment of Cognitive Brain Dysfunction in Chemical Dependence, Journal of Clinical Psychiatry, Vol. 45:60-63 (1984); Smith, Confirming Evidence of an Effective Treatment of Brain Dysfunction in Alcoholic Patients, Journal of Nervous and Mental Disease, Vol. 170:275-78 (1982) and Smith & Day, The Effects of Cerebral Electrotherapy on Short-Term Memory Impairment in Alcoholic Patients. International Journal of the Addictions, Vol. 12(4):574-82 (1977). However, the placement of the electrodes on the wrist and forehead, as disclosed herein, as opposed to the mastoids has greater beneficial effects on brain waves, in particular, increasing P300 wave amplitude in alcoholics and drug abusers. Both positions tend to normalize brain waves, but the placement of the electrodes on the forehead and wrist has the added beneficial effect on P300 wave amplitude.
The FDA has approved numerous CES devices for the treatment of anxiety, insomnia and depression. Several thousand patients are treated using CES devices annually in America. Existing CES devices are used by connecting electrodes to patients' mastoids, earlobes or temples. There have been anecdotal reports of studies using the CES device on the leg and the head. There have also been studies in which the electrodes have been connected to the temples, forehead, and eyelids, but not simultaneously to the wrist and the forehead. The connection of a CES device between the forehead and the wrist, stimulating the patient with a square wave at 100 Hz and a maximum of 1.5 mA to increase P300 wave activity does not appear to be taught or suggested by the prior art.